Reactive polyvinyl chloride and polymer products made therefrom

ABSTRACT

Thermoplastic polymers exhibiting improved physical properties and a method for preparing same are described. The method of preparing these polymer compositions comprises reacting a functionalized base polymer composition having pendant cyclic anhydride groups with a coreactive second moiety. Said functionalized base polymer comprises the reaction product of: 
     I. a hydroxyl containing base polymer comprising the reaction product of: 
     (a) a vinyl halide monomer; and 
     (b) at least one other ethylenically unsaturated monomer having at least one pendant hydroxyl functional group; and 
     II. a cyclic polyanhydride functionalizing agent.

This is a divisional of copending application(s) Ser. No. 07/276,175filed on 11/25/88

BACKGROUND OF THE INVENTION

1. Technical Field

This invention relates to polymers containing reactive functional groupsand to products obtained therefrom. This invention also relates to amethod for appending cyclic polyanhydride groups to vinyl halidepolymers by reacting a mixture of hydroxyl functionalized polyvinylhalide and a cyclic polyanhydride functionalizing agent. Thesefunctional copolymers are useful in the formation of a wide variety ofpolymer systems having a variety of physical and chemical propertiesthat may be tailored to specific end uses.

2. State of the Art

Polyvinyl halide resins particularly polyvinyl chloride (PVC) resinshave enjoyed a great deal of success as a material which may be formedinto a wide variety of useful articles. The ease at which PVC can bemolded, extruded, calendered or formed as well as its low cost, hascontributed to this success.

PVC by itself is a tough and hard polymer. To enable it to be processedinto useful articles, it has been proposed to add to the PVC processingaids, such as plasticizers and lubricants, or to form blends with othermonomeric and/or polymeric compounding ingredients. Processing aids arenormally incorporated into PVC during what is normally called acompounding operation. The PVC is worked on mill rolls and theprocessing aid(s) is added and milled into the polymer. This mixing canalso be performed with internal mixers or other mixing equipment all ofwhich is known in the art. PVC compositions made with processing aidsperform very well in most applications. However, these compositions havea tendency to migrate out of the PVC over extended periods of time. Thismigration phenomenon can lead to problems in some products. Forinstance, PVC will become more brittle as the plasticizer migrates out,thus leading to cracking and loss of flexibility of the PVC article. Incertain medical and food applications such as, for example, blood bags,medical tubing, food wrap and beverage containers, migrating processingaids may be extracted by the contents of the container leading tocontamination.

In another approach to the processing problem, it has been proposed toprepare blends of polymers which maximizes the processing and/orphysical properties of the component polymers. However, these attemptshave generally been unsuccessful. Blends of different types of polymersare often incompatible, resulting in a marked deterioration or loss ofphysical properties characteristic of each of the unblended polymers.The polymers tend to become cheesy during processing, making itextremely difficult to disperse any desired additives uniformlythroughout the blend. Even where the two polymer components arecompatible during melt processing, they often tend to separate intosegregated domains of individual polymer components.

Because of these drawbacks, various attempts have been undertaken toprepare polymer compositions that are easily processable and whichpossess improved physical properties. In this regard, many methods havefocused upon the preparation and use of functionalized polymers havingpendant reactive groups which facilitate the grafting of materials andother polymers to form graft-modified polymers and polymer blends havingimproved physical properties. The preparation of graft-modified resinsby grafting carboxyl-functionalities to a substrate polymer via thereaction of an anhydride and a polymer reactive therewith is known. Itis also known that the carboxyl-functionalized polymers thusly obtainedmay subsequently be further modified with compounds containing freehydroxyl groups. However, the prior art is directed to methods offorming carboxyl-containing polymers and products obtained thereby andnot to polymers containing pendant cyclic anhydride groups.

U.S. Pat. No. 4,382,128 discloses a method for preparingcarboxyl-modified polyolefins comprising the steps of: (1) reacting athermally degraded polyolefin with an unsaturated polycarboxylic acid,ester or anhydride which is graft polymerizable therewith; and (2)reacting the carboxyl-functionalized polymer thusly obtained with apolyhydroxy compound to obtain compositions having improved heatdistortion, strength and flexual modulus. The reaction of thepolyhydroxy compound with the carboxyl-functionalized polymer ispreferably conducted in the presence of solvents.

U.S. Pat. No. 4,506,056 discloses a method for preparingcarboxyl-containing polymers comprising mixing together maleicanhydride, a free radical copolymerization initiator, an additive whichinhibits the homopolymerization of maleic anhydride and a substratepolymer. The ingredients are mixed above the melting point of thesubstrate polymer in a suitable mixing device yielding acarboxyl-functionalized polymer. Suitable substrate polymers includevinyl halide, e.g., vinyl chloride.

In U.S. Pat. No. 4,680,361 there is disclosed a crosslinked polymercoating composition comprising carboxyl-functionalized lactoneacrylates. These compositions are derived from a reactive monomer unitprepared from the reaction of hydroxyalkyl acrylate andepsilon-caprolactone, said monomer unit is subsequently reacted with ananhydride to produce a monomer containing carboxyl groups. The monomerso prepared can be homopolymerized or copolymerized with otherethylenically unsaturated monomers, including vinyl halide.

Basically, however, all of the foregoing methods have disadvantages.Reacting a carboxyl-functionalized substrate polymer with a polyhydroxycompound in the presence of a solvent as disclosed in U.S. Pat. No.4,382,128 is disadvantageous from the standpoint that solvents aregenerally difficult to handle, pose environmental hazards and aredifficult to dispose of. The melt processable carboxyl-functionalizedpolymers disclosed in U.S. Pat. No. 4,506,056 require the addition offree radical initiators and certain polymerization inhibitors duringtheir preparation, leading to complex formulation problems. Moreover,the carboxyl-functionalized polymers thusly obtained would be difficultto derivatize with hydroxy containing materials due to the nature of thetransesterification reaction. Transesterification is an equilibriumreaction. To shift the equilibrium in the direction favoring products,it would be necessary to utilize large excesses of the hydroxycontaining compound or to remove products from the reaction medium. Thiswould require extra process steps and added operation costs.

The disadvantage inherent in the method taught in U.S. Pat. No.4,680,361 are the multitude of reaction products contained in thepolymer composition. For example, this patent is directed to crosslinkedcompositions comprising polymerizing one or more ethylenicallyunsaturated monomers with a composition comprising:

(a) 0 to 10 weight percent, preferably 0 to 5 weight percent of alactone;

(b) 0 to about 10 weight percent of hydroxyethyl acrylate ormethacrylate;

(c) 0 to about 2 weight percent, preferably 1 or less weight percent, ofone or more diacrylates;

(d) 0 to about 10 weight percent, preferably 5 or less weight percent,of products resulting from Michael addition, acrylate polymerization,transesterification reactions, or other side reactions;

(e) 0 to about 50 weight percent, preferably 0 to about 20 weightpercent, of a reactive monomer of the following average formula:##STR1## wherein R⁵ is a divalent radical, R² is either hydrogen ormethyl, each of R³ and R⁴ is hydrogen, phenyl, or lower alkyl having 1to about 6 carbon atoms, x is an integer having a value of up to about10, and y is an integer having a value up to about 20;

(f) 0 to 20 weight percent, preferably less than 10 weight percent, ofthe reaction product of hydroxyethyl acrylate or methacrylate and ananhydride; and

(g) remainder to 100 weight percent of reactive monomer of the followingaverage formula:

    CH.sub.2 ═CRCO.sub.2 R'--O[COR"--O].sub.m COR'"--[COOH].sub.z

wherein R is H, methyl or ethyl, R' is an alkylene radical having 2 toabout 12 carbons, R" is an alkylene radical having about 1 to about 10carbons, R'" is a divalent radical having 2 to about 20 carbons, m is aninteger having a value of 1 to about 20, preferably 1 to about 10, mostpreferably 1 to 5, and z is an integer having a value of 1 to about 4,preferably 1 to 2.

It is readily apparent from the foregoing that many competing sidereactions may occur during the homo- or copolymerization of the abovereactive monomer composition. For example, unwanted crosslinking mayoccur during the homo- or copolymerization of the reactive monomercomposition in the presence of the diacrylates as disclosed under item(c) above.

Accordingly, it would be highly desirable to provide a method forpreparing a polymer resin which is substantially pure and free frompolymerization contaminants and which has improved physical propertiesby means of an improved process which can be run in a single reactionvessel. None of the foregoing disclosures teach or suggest such a methodor polymer product obtained thereby.

SUMMARY OF THE INVENTION

In one aspect of the present invention there is provided a reactivevinyl halide base polymer composition which is functionalized with acyclic anhydride functionalizing agent.

In another aspect of the invention the functionalized base polymercomposition is reacted with a coreactive second moiety wherein acovalent bond(s) is formed between the functionalized base polymer andthe coreactive second moiety. Said coreactive second moiety beingselected to enhance the processability and physical properties of theresulting composition.

In a further aspect of the invention there is provided a hydroxylfunctional vinyl halide polymer that can be reacted with coreactivemonomeric and polymeric moieties resulting in a polymer composition withimproved physical properties.

In a still further aspect of the invention there is provided afunctionalized base polymer composition which may be crosslinked withoutfurther modification.

In another aspect of the present invention there is provided a polymercomposition having internally bound plasticizers, lubricants or impactmodifiers.

In another aspect of the present invention there is provided a methodfor forming compatible blends of polymers and the products obtainedthereby.

A still further aspect of this invention is a method of preparing apolymer composition which is free of competing side reactions.

These and other aspects of the present invention are accomplished hereinby a method and composition comprising the reaction product of:

I. a hydroxyl containing base polymer comprising the reaction productof:

(a) a vinyl halide monomer; and

(b) at least one other ethylenically unsaturated monomer having at leastone pendant hydroxyl group; and

II. a cyclic polyanhydride functionalizing agent to give afunctionalized base polymer; and

III. reacting said functionalized base polymer with a second moietycoreactive therewith, wherein the second coreactive moiety is covalentlybonded to the functionalized base polymer.

DETAILED DESCRIPTION

The present invention is directed to a method for functionalizing ahydroxyl or epoxy containing vinyl halide base polymer with a cyclicpolyanhydride and to the reaction products thereof that are useful inthe formation of a wide variety of polymer compositions.

For ease of definition the hydroxy containing base polymers and monomersas used herein and throughout the claims include epoxy-containing basepolymers and monomers.

The compositions of the present invention comprise the reaction productsof a functionalized base polymer and a coreactive second moiety. Thefunctionalized base polymer is a vinyl halide polymer having appendedcyclic anhydride groups which is obtained from the reaction of ahydroxyl containing vinyl halide copolymer and a cyclic polyanhydridefunctionalizing agent. The second reactive moiety contains at least onecoreactive group capable of forming covalent bonds with cyclicanhydrides, such as, for example, hydroxyl, oxazoline epoxy groups,lactam and secondary amine groups, e.g., --NH--, and the like. Thesecond reactive moiety may be monomeric or polymeric and the term asused herein refers to coreactive plasticizers, lubricants, impactmodifiers, heat distortion modifiers, processing aids and polymers orany other physical property modifier or processing aid utilized toimprove the physical characteristics and/or processability of the basepolymer.

The cyclic anhydride groups are present on the base polymer in acoupling amount, e.g., an amount which is sufficient to coreact with andcovalently bond a plasticizing, lubricating, impact modifying orimproved processing amount of the second reactive moiety. Of course, asis apparent to those skilled in the art, the amount of cyclicpolyanhydride functionality that is required to bind effective amountsof the second reactive moiety will depend somewhat on the particularpolymers and modifying aids employed, e.g., their miscibilities with thebase polymer, the level of coreactive moiety to be bound and the levelof coreactive groups on the coreactive moiety. In general, a couplingamount of cyclic anhydride is present when the repeating units of thebase polymer containing the appended cyclic anhydride groups (e.g.hydroxyl containing groups) comprise from about 1 to about 49 percent byweight of the base polymer composition and preferably from 1 to 20percent by weight of the base polymer composition.

As previously indicated, the functionalized base polymers of the presentinvention are obtained from the reaction product of a hydroxylcontaining vinyl halide copolymer and a cyclic polyanhydride. Thehydroxyl containing vinyl halide base polymers of the present inventioncomprise repeating units of vinyl halide and hydroxyl or epoxycontaining vinyl components. As used herein, the term vinyl halideincludes vinyl chloride and vinylidene halides, such as, for example,vinylidene chloride and any other vinylidene halide having at least oneterminal CH₂ ═C< group. The hydroxyl containing vinyl component includeshydroxyalkyl acrylates and methacrylates such as, for example,hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropylacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate,hydroxybutyl acrylate and 3-chloro-2-hydroxypropyl methacrylate and thelike and acrylated caprolactones (e.g., polycaprolactones) havingrepeating units represented by the following average formula: ##STR2##wherein R is hydrogen, lower alkyl, or phenyl, R₁ and R₂ are,independently, alkylene of 1 to about 8 carbon atoms and n is 1 to about20. Lower alkyl as used herein refers to branched or straight chainalkyl groups of 1 to 6 carbon atoms. It should be evident to thoseskilled in the art that n, as used herein, represents an average of thecaprolactone molecules per acrylate group. It is also contemplated thatfractional values of n between 1 and 20 are within the scope of thisinvention. The epoxy containing vinyl component includes epoxy acrylatesand epoxy methacrylates such as, for example, glycidyl acrylate andglycidyl methacrylate.

The preferred acrylated caprolactone monomers utilized in the presentinvention may be prepared by the reaction of the appropriate acryloylchloride, e.g., with diol terminated polycaprolactones. Methods forpreparing acrylated caprolactones are disclosed in copending U.S. patentapplication Ser. No. 046,818, filed on May 7, 1987 which is herebyincorporated by reference. Other methods for preparing acrylatedcaprolactones are disclosed in U.S. Pat. No. 4,504,635. The preferredacrylated caprolactone comonomers are those derived from 2-hydroxyethylacrylate and methacrylate, which may be represented by the followingaverage formula: ##STR3## wherein R is methyl or hydrogen and n is 1 to20.

The preferred acrylated polycaprolactones and non-acrylatedpolycaprolactone precursors are commercially available from variousmanufacturers. For example, acrylated and non-acrylated caprolactonesare manufactured and sold by Union Carbide Corp. under the TONE®trademark. Representative formulas are set forth below.

    ______________________________________                                        ACRYLATED AND NON-ACRYLATED                                                   POLYCAPROLACTONES                                                             TONE ® Monomer                                                                         Approximate No. of                                                                           Approximate                                       Designation  Repeating Units (n)                                                                          Molecular Wt.                                     ______________________________________                                        XM-100       1              230                                               M-100        2              340                                               0200*        4-6            500                                               0240*        16-18          2000                                              ______________________________________                                         *Acrylated monomer was prepared inhouse by reacting the appropriate TONE      polyol with acryloyl chloride.                                           

The hydroxyl containing vinyl halide base polymer compositions of thepresent invention are prepared by conventional polymerization techniquesin which vinyl halide monomers are copolymerized with hydroxylcontaining vinyl comonomers, polymerization catalysts, and if desired,chain transfer agents. The comonomers may be polymerized by any one of avariety of polymerization techniques including mass polymerization,suspension polymerization, or microsuspension polymerization via thepolymerization reaction of the ethylenically unsaturated groups of therespective monomers. The preferred process, however, for preparing thebase polymers according to this invention is via suspensionpolymerization. Suspension polymerization techniques are well-known inthe art as set forth in the Encyclopedia of PVC, pp. 76-85 published byMarcel Decker, Inc. (1976) and need not be discussed in great detailhere. Generally, the comonomers are suspension-polymerized in an aqueousmedium containing: (1) a suspending agent consisting of one or morewater-soluble polymer substances such as polyvinyl alcohol, celluloseether, partially hydrolyzed polyvinyl acetate, vinyl acetate-maleicanhydride or partially saponified polyalkyl acrylate or gelatine, and(2) a polymerization initiator. Suitable polymerization initiators areselected from the conventional free radical initiators such as organicperoxides and azo compounds. The particular free radical initiator willdepend upon the monomeric weight and color requirements of the copolymerand the temperature of the polymerization reaction. Insofar as theamount of initiator employed is concerned, it has been found that anamount in the range of about 0.005 part by weight to about 1.00 part byweight, based on 100 parts by weight of vinyl halide comonomer beingpolymerized, is satisfactory. It is preferred to employ an amount ofinitiator in the range of about 0.01 part by weight to about 0.20 partby weight, based on 100 parts by weight of vinyl halide monomer.Examples of suitable initiators include lauroyl peroxide, benzoylperoxide, acetyl cyclohexyl sulfonyl peroxide, diacetyl peroxide, cumenehydroperoxides, 5-butyl peroxyneodecanoate, alpha-cumylperoxyneodecanoate, t-butyl cumyl peroxyneodecanoate, t-butylperoxypivalate, t-butyl peroxyacetate, isopropyldicarbonate, di-n-propylperoxydicarbonate, disecondary butyl peroxydicarbonate,2,2'-azobis(2,4-dimethyl valeronitrile), azobisisobutylnitrile,α,α'-azodiisobutyrate and t-butyl perbenzoate, the choice depending onthe reaction temperature.

The suspension polymerization process of this invention may be carriedout at any temperature which is normal for the copolymer to bepolymerized. A temperature range from about 0° C. to about 80° C. isemployed. Preferably, a temperature range from about 40° C. to about 70°C. may be employed with a range from about 50° C. to about 60° C. beingthe most preferable. So far as the temperature is within these ranges,they may be varied in the course of the polymerization. In order tofacilitate temperature control during the polymerization process, thereaction medium is kept in contact with cooling surfaces cooled bywater, brine, evaporation, etc. This is accomplished by employing ajacketed polymerization reactor wherein the cooling medium is circulatedthrough the jacket throughout the polymerization reaction. This coolingis necessary since most all of the polymerization reactions areexothermic in nature. It is understood of course, that a heating mediummay be circulated through the jacket, if necessary.

Lower molecular weight base polymers may optionally be efficiently andeffectively produced is one of the preferred advantages of the presentinvention. By low molecular weight what is meant is that the inherentviscosities of the copolymers of the present invention range from about0.1 to about 0.7. The inherent viscosity is a representative measure ofthe molecular weight of a polymer and is obtained in accordance withASTM procedure No. D-1243-66. It is recognized that the processabilityof vinyl halide polymers and particularly a vinyl chloride polymerdepends to a large extent upon its average degree of polymerization.Polymers having relatively low molecular weights or low inherentviscosities are generally the easiest to fabricate because of their lowmelt viscosities, low shear sensitivity, good heat stability under highshear, and excellent flow characteristics. Because of these desirableprocessing characteristics, low molecular weight vinyl chloride typepolymers are widely used in applications in which they are injectionmolded or extruded to form products that may have thin walls, largesurface areas, and deep-draw and/or intricate surface detailed parts.

Specifically, the preferred suspension process of this inventionutilizes a chain transfer agent (CTA) to produce the low molecularweight base polymers of this invention. Suitable chain transfer agentsapplicable for this purpose are, for example, saturated hydrocarbons,such as saturated or unsaturated chlorinated hydrocarbons, such ascarbon tetrachloride, trichloroethylene and perchloroethylene,aldehydes, such as propionaldehyde and n-butylaldehyde and certainmercapto-containing organic compounds. The most preferred CTA, however,comprises a composition of: (a) at least one mercaptan chain transferagent and optionally (b) at least one non-polymerizable material whichis miscible with the mercaptan chain transfer agent. Suitable mercaptansfor the practice of this invention include water soluble mercaptans suchas 2-mercaptoethanol, 3-mercaptopropanol, thiopropyleneglycol,thioglycertine, thioglycolic acid, thiohydracyclic acid, thiolactic acidand thiomalic acid, and the like. Suitable non-water soluble mercaptansinclude isooctyl thioglycolate, n-butyl 3-mercaptopropionate, n-butylthioglycolate, glycol dimercaptoacetate, trimethylolpropanetrithioglycolate, bis-(2-mercaptoethyl) ether, alkyl mercaptans, and thelike. The most preferred mercaptan for use in the present invention is2-mercaptoethanol (2-ME), however, any chain transfer agent having oneor more mercapto (--SH) group(s) would be acceptable.

The chain transfer composition may be pre-mixed with the comonomer toencapsulate the mercaptan chain transfer agent before its introductioninto the reactor. Alternatively, the chain transfer agent may bepre-mixed with a non-polymerizable material which is miscible with thechain transfer agent and is substantially insoluble in water. The termnon-polymerizable as used herein means that the material does not form apart of the vinyl polymer backbone in the sense that a traditionalcomonomer would form. The non-polymerizable material may, in some cases,graft polymerize onto the vinyl polymer chain but this is not normallyconsidered a copolymer. The term substantially insoluble in water asused in this specification means that the materials have less than 5%solubility in water. The non-polymerizable material may be a monomer,oligomer or a polymer. Suitable non-polymerizable materials includedioctyl phthalate, low molecular weight poly (caprolactone),polysilicones, esters of glycerols, polyesters, water insoluble estersof fatty acids with --OH terminated polyoxyethylene andpolyoxypropylene, esters of polyols, esters of monoacids and polyacids,esters of organic polyphosphates, phenyl ethers, ethoxylatedalkylphenols, sorbitan monostearate and sorbitan monooleate and othersorbitol esters of fatty acids. Usually, the chain transfer compositionmust contain at least an equal amount in weight of non-polymerizablematerial as chain transfer agent in order to encapsulate or host thechain transfer agent. Preferably, the composition contains at leasttwice as much weight of non-polymerizable material as chain transferagent.

The amounts of chain transfer agent employed in the practice of both thecomonomer and non-polymerizable material encapsulant embodiments of thepresent invention range from 0.05 to 2.0 phm by weight per 100 phm ofvinyl halide comonomer. Preferably from 0.1 to 1.0 phm by weight per 100phm of vinyl halide comonomer may be employed. Most preferably 0.1 to0.8 phm by weight per 100 phm of vinyl halide comonomer may be utilized.The chain transfer agent may be added to the reaction medium before theonset of polymerization or it may be metered in during the course of thepolymerization reaction in combination with the comonomer.

The terms "encapsulation", "encapsulate" and "encapsulating" as usedherein mean that the CTA is homogeneously mixed with the comonomer ornon-polymerizable material.

The preferred polymerization initiators utilized in the process forpreparing the low molecular weight copolymers of the present inventionare alpha-cumyl peroxyneodecanoate, t-cumyl peroxyneodecanoate, t-butylperoxypivalate and t-amyl peroxyneodecanoate or combinations thereof.Most preferably, a dual initiator composition comprising alpha-cumylperoxyneodecanoate and t-butyl peroxypivalate is utilized as theinitiator. This initiator system results in a reduced residual initiatorlevel in the final product and a shorter high temperature history due tofaster reactions.

The concentration of hydroxyl containing vinyl comonomer in thepolymerization medium can range from about 1 to about 49 phm by weightbased upon 100 phm by weight of vinyl chloride monomer. The polymerizedbase polymer contains from about 1 to about 49 percent by weight ofhydroxyl containing components. Preferably the polymerized base polymercontains from about 1 to about 20 weight percent of hydroxyl containingcomponents. Typically the hydroxyl content of the base polymer rangesfrom about 0.1 to about 25 mole percent and preferably from about 0.5 to15 mole percent. In order to obtain a uniform copolymer (e.g. torandomize the distribution of hydroxyl groups along the copolymerbackbone), it is preferable to meter the hydroxyl containing comonomerinto the reaction medium during the course of the polymerization. Ofcourse, if a low molecular weight copolymer is desired, the appropriateCTA is utilized in the reaction medium as previously set forth.

The hydroxyl containing vinyl halide base polymers so prepared arefunctionalized with a cyclic polyanhydride functionalizing agent. Thereaction between the base polymer and functionalizing agent occurs underthe appropriate conditions to form a functionalized base polymer withappended cyclic anhydride groups. The term polycyclic anhydride as usedherein refers to an organic molecule containing at least two cyclicanhydride reactive groups. At least one cyclic anhydride group of thefunctionalizing agent is available to coreact with the hydroxyl or epoxygroup(s) situated on the base polymer, while the other cyclic anhydridegroup(s) remains available for further reaction. In other words, suchgroups serve as attachment vehicles capable of covalently coupling thesecond reactive moiety to the base polymer. The functionalizing agentmay be monomeric or polymeric. Examples of cyclic polyanhydridefunctionalizing agents useful in the present invention are as follows:5-(2,5-dioxotetra-hydro-3-furanyl)-3-cyclohexene-1,2, dicarboxylicanhydride (CAS Registry No. 73003-90-4); one tetracarboxylic dianhydride(CAS Registry No. 2421-28-5); 1,2,4,5-benzene-tetracarboxylic anhydride(CAS Registry No. 89-32-7); 3,4,3',4'-biphenyltetracarboxylicdianhydride (CAS Registry 2420-87-3); glycerol acetate bistrimellitate(dianhydride) (CAS Registry No. 1732-97-4); and ethylene glycolbistrimellitate (dianhydride) (CAS Registry No. 1732-96-3). Theforegoing polyanhydrides are available from commercial suppliers suchas, for example, the Chriskev Company, Inc. of Leawood, Kans.

It should also be understood that polymeric cyclic polyanhydridesincluding copolymeric cyclic polyanhydrides are useful asfunctionalizing agents in the present invention. Examples of suchcopolymers which can be successfully employed in this invention includealkyl vinyl ether/maleic anhydride copolymers and styrene/maleicanhydride copolymers. The formula of the copolymeric alkyl vinyl etheris as follows: ##STR4## wherein R is lower alkyl, a and b independentlyare integers ranging from 1 to about 100 and m has a value such that themolecular weight of the copolymer is between about 1000 to about200,000.

Useful styrene/maleic anhydride copolymers are represented as follows:##STR5## wherein c and d independently are integers ranging from 1 toabout 100 and n has a value such that the molecular weight of thecopolymer is between about 400 to about 200,000 and preferably fromabout 1000 to about 50,000. Generally, the maleic anhydride content ofthe copolymer may range from about 1 to about 50 percent by weight ofthe total copolymer. Methyl vinyl ether/maleic anhydride copolymers arecommercially available from suppliers such as, for example, the GAFCorporation under the trademark GANTREZ® (AN Series). The styrene/maleicanhydride copolymers are commercially available from suppliers such asArco Chemical under the DYLARK® and SMA 3000A trademarks. Otherpolymeric functionalizing agents include alkylene/maleic anhydridecopolymers, cycloalkylene/maleic anhydride copolymers, maleicanhydride/alkyl acrylate and methacrylate copolymers and maleicanhydride/alkyl acrylamide copolymers and the like.

The styrene/maleic anhydride copolymers may optionally contain othermonomers as well as other polymers. Copolymers of styrene and maleicanhydride can contain monomers such as butadiene and terpolymers such asacrylonitrile/butadiene/styrene. Such terpolymer compositions arecommercially available from Monsanto Corporation and Arco Chemical underthe trademarks CADON® 300 series (e.g., 322, 330, 332 and 340) andDYLARK® 700 respectively. CADON compositions are described in U.S. Pat.No. 4,223,096. DYLARK-700 contains about 83 weight percent styrene, 7.5weight percent maleic anhydride and 9.1 weight percent polybutadiene.

Generally, the hydroxyl containing base polymer and the functionalizingagent are brought into contact with each other under intensive shear andelevated temperature conditions to yield the functionalized basepolymer. The amount of cyclic polyanhydride needed to functionalize thebase polymer will depend, of course, on the amount of hydroxylfunctionality present on the base polymer backbone. To fullyfunctionalize the base polymer backbone at least a 1:1 molar ratio offunctionalizing agent to hydroxyl functionality should be employed. Toensure complete functionalization of the base polymer thefunctionalizing agent should be employed in slight molar excess.However, lesser amounts of functionalizing agent may be utilized ifdesired. The functionalized base polymer may then subsequently bereacted under these same conditions with the second reactive moiety togive the final modified polymer product. In practice, the base polymeris functionalized by melt blending the hydroxyl containing vinyl halidecopolymer and functionalizing agent in conventional melt blendingequipment such as a two-roll mill, Brabender Plasticorder, a single ormultiple screw extruder, or any other of the well-known thermalmechanical mixing devices normally used in the mixing, compounding,processing or fabricating of thermoplastic polymers. The hydroxycontaining base polymers are functionalized at temperatures between 250°and 350° F. It is important that this reaction be conducted underanhydrous conditions (including the use of anhydrous ingredients) so asnot to hydrolyze the cyclic anhydride groups on the polyanhydridefunctionalizing agent. The functionalized base polymer thusly obtainedmay then be further modified to desired end product specifications bycoreacting it under heat and shear with the desired second reactivemoieties, e.g., coreactive plasticizers, lubricants, impact modifiers,processing aids and coreactive polymer blends. In practice, a mixture ofbase polymer and functionalizing agent (and, if desired, optionaladditives as set forth below) are mixed at a reaction temperature abovethe softening point of the base polymer resin (250° to 350° F.) wherethe mixture undergoes deformation and is converted to a molten state,e.g., to a fluid or semi-fluid state. Alternatively, the functionalizingagent and desired additives may be added to the molten base polymer. Themixture of reactants is subjected to mechanical deformation in asuitable mixing device such as a Brabender Plasticorder, a two-rollmill, a single or double screw extruder or any other of the well-knownmechanical mixing equipment normally utilized in the mixing,compounding, processing or fabricating of thermoplastic polymers. Thefunctionalization reaction is fairly rapid and is completed to a majorextent approximately 1 to 5 min. after the ingredients reach the moltenstate. Coreactive second moieties can then be added to thefunctionalized base polymer undergoing deformation in the mechanicalmixing device. The coreactive second moiety may be added continuously orin several portions over a period of time to promote homogeneous andcomplete reaction throughout the mixture. The reaction is generallycomplete approximately 5 min. after the coreactive moiety has been addedto the functionalized base polymer.

The coreactive moieties of the present invention are reacted insufficient amounts whereby substantially all cyclic anhydride groups onthe base polymer are reacted to form covalent linkages with thecoreactive moiety. The molar ratio of coreactive functional groups onthe coreactive second moiety to cyclic anhydride groups on thefunctionalized base polymer should preferably be 1:1 to ensure completereaction of the cyclic anhydride groups. As indicated previously, thelevel of coreactive second moiety to be bound will dictate the level ofcyclic polyanhydride functionalization of the base polymer andultimately the level of hydroxyl functionalization to employ in thepreparation of the hydroxyl containing vinyl halide base polymer.Accordingly, it is important to employ a base polymer having sufficientlevels of functionalization to react with and bind effective amounts ofthe coreactive second moiety.

The particular type of coreactive moiety to be reacted with thefunctionalized base polymer will depend upon the desired end use of thecomposition. Any compound containing a functional group that iscoreactive with a cyclic anhydride groups may be utilized so long as thecompound produces the desired physical properties. For example, when acomposition must exhibit a high degree of plasticization with lowmigration of plasticizer, polyester plasticizers containing terminalhydroxyl groups may be coreacted with the functionalized base polymersof the invention. The terminal hydroxyl groups on the polyester coreactwith the cyclic anhydride groups on the functionalized base polymerforming an internally plasticized, e.g., permanently plasticized,polymer composition. Particularly useful plasticizers are PLASTHALL®P-1070 and ADMEX® 2056, hydroxyl terminated polyesters from the C. P.Hall Company and Nuodex, Inc. respectively, and TONE® caprolactonepolyols such as TONE 0240 available from Union Carbide.

Epoxy type materials with and without curing agents may also be utilizedin the present invention. Examples of epoxy materials are epoxidizedsoybean and linseed oils, cycloaliphatic epoxides, such as ERL-4221 byUnion Carbide, aliphatic epoxides, such as FL313 by Kishimoto SangyoCompany of Japan and EPON® epoxy resins by Shell Chemical Company.Suitable epoxy curing agents known in the art of epoxy curing such as,for example, the amine curing agents may be utilized in conjunction withthe epoxy resins of the present invention.

Any plasticizer containing free hydroxyl groups or epoxide groups may beutilized so long as the plasticizer is compatible with the base polymer.Suitable levels of coreactive plasticizer to be utilized in the presentinvention will range from about 1 to about 100 phr and preferably fromabout 40 to about 80 phr.

When it is desirable to reduce the melt viscosity or increase theprocessability of the present base polymer compositions, permanentlybound lubricants may be incorporated therein. In this way the lubricantwill not migrate out of the finished product. In selecting a coreactivelubricant it is important that it be only slightly compatible with thebase polymer. Too much compatibility will lead to plasticization of thebase polymer resin instead of lubrication and such resin would not beuseful where rigid properties are desired. Any lubricant useful in thelubrication of vinyl polymers may be utilized so long as it contains acoreactive functional group. Of particular interest are the fattyalcohol containing lubricants such as, for example, 9,10-dihydroxystearic acid, 12-hydroxy stearic acid, lithium 12-hydroxy stearate,1-eicosanol, 1-octadecanol, 1-hexadecanol, 1-tetradecanol, 1-dodecanol,and 2-dodecanol. These lubricants are normally volatile and consequentlyevaporate under conventional processing conditions in the polymer melt.The method of the present invention is a way to covalently bond suchlubricants to the base polymer composition consequently reducing theirvolatility during processing.

Other lubricants useful in the present invention are the silanolterminated polysiloxanes having the following structure: ##STR6##wherein n is 1 to 100

Suitable levels of coreactive lubricant to be utilized in the presentinvention will range from about 0.1 to 10 phr and preferably from 0.1 toabout 5 phr.

Through the method of the present invention impact modifiers may easilybe grafted to the functionalized base polymers of the present invention.As is well-known in the polymer art impact modifiers are incompatible orsemi-compatible discontinuous domains of rubbery type polymers which arehomogeneously dispersed throughout a continuous polymer phase. Foroptimum performance, the impact modifier must resist the formation of asingle phase system with the polymer within which it is dispersed. Theimpact modifier must also be sufficiently compatible with the polymer toadhere to the polymer at the polymer-impact modifier interface. Thecoreactive groups on the functionalized base polymer and on the impactmodifier serve to provide a compatible interface. Any impact modifierwhich contains or which can be modified to contain pendant functionalgroups coreactive with cyclic anhydrides may be utilized herein.Suitable levels of coreactive impact modifiers to be utilized in thepresent invention will range from about 5 to 50 phr and preferably from5-30 phr.

Polymer blends comprising the functionalized base polymer of the presentinvention and a second coreactive polymer may be prepared in accordancewith the method of this invention. The second reactive polymer moietycan be one of any thermoplastic polymers which contain or can bemodified to contain a coreactive group as hereinbefore described.Polymers such as olefins, vinyl halides, vinylidene halides, acrylicesters and monovinylidene aromatics may be utilized. In order to beuseful, the second reactive polymer moiety should generally be acopolymer made up of at least some monomer units which contain a pendantcoreactive group. For example, polymers can be copolymerized from acomonomer containing a pendant hydroxyl group such as those previouslydescribed. Comonomers containing pendant oxazoline groups such as, forexample, 2-alkenyl-2-oxazolines (hereinafter referred to as oxazoline),especially 2-isopropenyl-2-oxazoline are also useful. Such copolymersare described in U.S. Pat. Nos. 3,380,975 and 3,505,297. Reactivepolystyrene (M.W. 200,000, specific gravity 1.04) containing 1 percentoxazoline functionality is commercially available from Dow Chemical.Comonomers containing epoxy functionalities such as glycidyl acrylateand methacrylate and the like may also be utilized. Reactive terpolymerssuch as styrene/acrylonitrile/oxazoline (RSAN) may be employed and arecommercially available from Dow Chemical. Polymers containing thesecondary amine groups, (e.g. --NH--), such as, for example, variouspolyurethanes, polyamides, polypeptides and polymers derived fromcaprolactams, ureaformaldehydes, melamineformaldehydes and the like maybe utilized in the blends of the present invention. Hydroxyl containingpolymers such as hydroxyl containing polystyrene, hydroxyl containingstyrene/acrylonitrile copolymer, hydroxyl containingstyrene/acrylonitrile/α-methyl styrene terpolymer and hydroxylcontaining polyolefins may also be utilized.

The polymer blends of the present invention can be prepared using wideranges of functionalized base polymer components. By varying theproportion of pendant cyclic anhydride groups on the base polymer and byvarying the type and amount of the second polymer moiety, the propertiesof the resultant blend can be engineered to many desired specifications.The coreactive groups on the functionalized base polymer and secondpolymer moieties serve to compatibilize the blend of respectivecomponents. Of course, the more compatible the respective polymerbackbones are, the less the need for compatibilizing coreactive groups.Since, as described in more detail hereinbefore, the cyclic anhydrideforms a covalent linkage with the coreactive group on the second polymermoiety, it is readily seen that the degree of compatibilization of thepolymer blends can also be controlled with the proportion of cyclicanhydride functional groups present in the blend. As also discussedabove, the level of anhydride functionality on the functionalized basepolymer ultimately depends upon the hydroxyl level present on the basepolymer component.

In another aspect of the present invention, the method described hereincan be utilized to provide a crosslinked polymer composition. In thisembodiment, the cyclic anhydride functionalized base polymer can bereacted with any of the hydroxy containing base polymers describedherein. Alternatively, the hydroxyl containing base polymers can bemixed on the thermal mixing equipment described hereinabove with thecyclic polyanhydride functionalizing agent. The functionalizing agent ineffect functions as a crosslinking agent. Crosslinking may also beutilized to ensure that a coreactive second moiety becomes permanentlybound within the polymer matrix. For example, an internally plasticizedcomposition can be produced by reacting a hydroxyl containingplasticizer with a functionalized base polymer, herein described, toyield a plasticized base polymer having pendant hydroxyl groups. Theplasticized base polymer having pendant hydroxyl groups on theplasticizer moiety can be functionalized with cyclic polyanhydride andsubsequently coreacted with additional plasticized base polymer havingpendant hydroxyl groups to yield a crosslinked, plasticized polymercomposition as exemplified in Example 24.

It should be readily apparent from reading and understanding thedisclosure herein that any of the hydroxyl containing base polymers ofthis invention can also be reacted with any cyclic anhydride containingmoiety to form desired end products. For example, hydroxy containingvinyl halide base polymers may be reacted with the DYLARK and SMA 3000Astyrene/maleic anhydride copolymers as well as impact modifiedstyrene/maleic anhydride terpolymers such as the CADON® polymers fromMonsanto. These terpolymers are described and prepared according to U.S.Pat. No. 4,223,096. Such compositions exhibit improved heat distortionproperties. The hydroxyl containing base polymers can also be reactedwith maleic anhydride modified ethylene/propylene copolymers which arecommercially available from Himont U.S.A. and Exxon under thetrademarks, PRO-FAX® SB222PM and VISTALON® XX1601, respectively.

In addition to the internally bound plasticizers, lubricants, processingaids and polymer blends etc., the compositions of the present inventionmay also contain optional compounding ingredients which are conventionalin the preparation of compounded resins. Typically, these additivesinclude stabilizers, plasticizers, lubricants, processing aids and thelike which are well known in the polymer compounding art and need not bedescribed here.

The following examples will show one skilled in the art how to operatewithin the scope of the present invention and are not intended to serveas a limitation on the scope of this invention for such scope is definedonly in the claims. In these examples, all parts are parts by weight andall percentages are percentages by weight.

EXAMPLES 1-9

To a two-roll mill heated to 280° F. was added 100 parts of a hydroxylcontaining base polymer resin (1.2 mole % hydroxyl content) comprising acopolymer of vinyl chloride/acrylated caprolactone (6.3 wt. % TONEM-100). The base polymer was functionalized by adding the cyclicpolyanhydride functionalizing agents in the proportions shown in Table 1and milling for 2 to 4 min. To the functionalized base polymer was addedthe various coreactive second moieties also set forth in Table I. Thecomponents were milled for an additional 5 to 15 min.

To show that the coreactive second moieties are covalently grafted ontothe functionalized base polymer thus giving an internally modifiedpolyvinyl copolymer (e.g., the coreactive second moiety cannot betotally extracted out of the resin), a 1 to 2 gram sample of eachpolymer blend was pressed into a thin sheet 30 mils thick by 3 inches indiameter. Each sample was immersed in 75 g of n-butyl chloride for 24hrs., removed and then dried in a vacuum oven at 60° C. for 24 hrs. andweighed. The amount of extracted second moiety was calculated bycomparing the weight loss of the extracted sample to the original weightof the sample before extraction. The results are given in Table I.

                                      TABLE I                                     __________________________________________________________________________    Functionalizing Agent                                                                              Coreactive Moiety                                                                            Percent of Extractable                    Example                                                                            Type      Level (phr)                                                                         Type     Level (phr)                                                                         (less) Coreactive Moiety                  __________________________________________________________________________    1    EPICLON.sup.1 B-4400                                                                    6.7   TONE 0240.sup.3                                                                        50.0  2.1                                       2    EPICLON B-4400                                                                          6.7   TONE 0240                                                                              55.3  0                                         3    AC-32.sup.2                                                                             6.7   TONE 0240                                                                              55.3  37                                        4    EPICLON B-4400                                                                          6.7   ESO      50.0  0                                         5    AC-32     6.7   ESO      63.0  23.0                                      6    EPICLON B-4400                                                                          6.7   PLASTHALL                                                                              50.0  41.0                                                           P-1070                                                   7    EPICLON B-4400                                                                          12.0  PDMS PS339.7.sup.4                                                                     33.3  0.sup.5                                   8    EPICLON B-4400                                                                          7.5   ADMEX 2056                                                                             60.0                                            9    CONTROL.sup.6                                                                           --    TONE 0240                                                                              55.5  67.8                                      9A   CONTROL.sup.6,7                                                                         --    TONE 0240                                                                              55.5  76.3                                      __________________________________________________________________________     .sup.1 Trademark of Dainippon Ink & Chemicals                                 (5(2,5-dioxotetrahydro-3-cyclohexene-1,2-dicarboxylic anhydride)              .sup.2 Glycerol acetate bistrimellitate (dianhydride)                         .sup.3 Nonacrylated                                                           .sup.4 Silanol terminated polysiloxane M.W. 400700 (Petrarch Systems,         Inc.)                                                                         .sup.5 Weight gain of 4.9%                                                    .sup.6 GEON 110 × 450 PVC homopolymer (I.V. = .95)                      .sup.7 Non reactive due to lack of functionalizing agent                 

EXAMPLES 10-15

These examples illustrate that the grafting of the coreactive secondmoiety can be effected through the coreaction of the hydroxyl containingbase polymer and an anhydride containing second moiety as well asthrough a functionalized base polymer.

The compositions were prepared as set forth in examples 1-8 except thatthe mill temperature was 300° F. Conventional tin stabilizer andoxidized polyethylene lubricant processing aids were added to the resinmixture before milling. The hydroxyl containing base polymer (3.2 wt. %TONE M-100) had a 0.6 mole % hydroxyl content. The I.V. of the resin was0.46.

The compositions were qualitatively rated for processability on the millduring the 3 min. period following the addition of the coreactive secondmoiety. Due to crosslinking, excessive processing increases meltviscosities leading to hard processing. Processability was rated as verysoft, soft and hard (soft being the most desirable and hard being theleast desirable). Heat distortion temperature (HDT) of 1/8 in. thickbars were evaluated for each example in accordance with ASTM D-648.(Samples annealed @ 90° C. for 24 hrs.)

The results set forth in Table II indicate that the compositions of thepresent invention have improved processability over PVC homopolymerwhile maintaining good heat distortion properties.

                                      TABLE II                                    __________________________________________________________________________           Functionalizing Agent                                                                      Coreactive Moiety                                         Example                                                                              Type   Level (phr)                                                                         Type    Level (phr)                                                                         Processability                                                                       HDT (°C.)                     __________________________________________________________________________    10      --    --    CADON 330.sup.4                                                                       34    Soft   65.0                                 11      --    --    CADON 332.sup.5                                                                       34    Soft   65.0                                 12     SMA 3000A.sup.1                                                                      34     --     --    Very Soft                                                                            69.5                                 13     SMA 3000A                                                                            10    RSAN.sup.6                                                                            25    Soft   69.0                                 14     AC-32  5.8   RSAN    25    Soft   70.5                                 15     AC-32  6.0   EPON 1002F.sup.7                                                                      20    Very Soft                                                                            68.5                                 CONTROL                                                                              hydroxyl containing base polymer.sup.2                                                                   Soft   63.0                                 CONTROL                                                                              PVC homopolymer.sup.3      Hard   69.0                                 __________________________________________________________________________     .sup.1 Styrene/maleic anhydride copolymer (Acid No. 275) Arco Chemical        .sup.2 0.6 mole % hydroxyl content                                            .sup.3 GEON 110 × 377 resin (I.V. = 0.53), B F Goodrich                 .sup.4 Impact Modified Styrene/maleic anhydride copolymer, Monsanto Corp.     .sup.5 Styrene/maleic anhydride copolymer, Monsanto Corp.                     .sup.6 Styrene/acrylonitrile/oxazoline terpolymer (1 wt. % oxazoline          content)                                                                      .sup.7 2,2bis(p-glycidyloxyphenyl) propane condensation product with          2,2bis(p-hydroxyphenyl) propane, Shell Chemical                          

EXAMPLES 16-22

The compositions of the following examples were prepared and evaluatedas described in examples 10-15 except that the hydroxyl content of thebase polymer was about 1 mole % (1.8 wt. % 2-hydroxylethyl acrylate)with an I.V. of 0.45. The compositions were made with conventionalprocessing aids and stabilizers and milled at 320° F. Results are givenin Table III.

                                      TABLE III                                   __________________________________________________________________________           Functionalizing Agent                                                                         Coreactive Moiety                                      Example                                                                              Type      Level (phr)                                                                         Type    Level (phr)                                                                         Processability                                                                       HDT (°C.)                  __________________________________________________________________________    16     EPICLON B-4400                                                                          12.0  EPON 1002F                                                                            40.0  Very Soft                                                                            76.5                              17     EPICLON B-4400                                                                          12.0  EPON 1002F                                                                            80.0  Very Soft                                                                            76.0                              18     --        --    DYLARK 290                                                                            23.3  Soft   69.5                              19     --        --    DYLARK 290                                                                            66.7  Soft   75.0                              20     --        --    RSAN    70.0  Soft   71.5                              21     SMA 3000A 16.7  RSAN    70.0  Soft   77.5                              22     SMA 3000A  9.3  RSAN    70.0  Soft   77.5                              CONTROL                                                                              hydroxyl containing base polymer.sup.1                                                                      Soft   63.0                              __________________________________________________________________________     .sup.1 1.0 mole % hydroxyl content                                       

EXAMPLE 23

To a two-roll mill was added 100 parts of a base polymer containing 2.17mole percent hydroxyl content (10.8 wt. % TONE M-100) and the amounts offunctionalizing agent indicated in Table IV. The ingredients were milledat 300° F. for 5 min. to obtain a functionalized base polymer. 70 phr ofpolymeric plasticizer (TONE 0240) was then added to the functionalizedbase polymer composition and milled for an additional 14 min. Theinternally plasticized composition was then evaluated for extractablesand compression set properties in accordance with examples 1-8 and ASTMD395-61, respectively. Results are shown in Table IV.

EXAMPLE 24

125 g. of the plasticized polymer composition of Example 23 wasadditionally functionalized with the functionalizing agent set forth inTable IV. The functionalizing reaction was carried out on a two-rollmill at 300° F. for 4 min. To the functionalized plasticized compositionwas then added 125 additional grams of the compound of Example 23. Theingredients were milled for an additional 4 min. Following the millingthere was obtained a crosslinked internally plasticized polymercomposition. The composition was evaluated as in Example 23. Results aregiven in Table IV.

                  TABLE IV                                                        ______________________________________                                                            % of                                                             Functionalizing Agent                                                                      Extractable                                                                   Level   (loss)  Compression                               Example  Type       (phr)   Plasticizer                                                                           Set %                                     ______________________________________                                        23       EPICLON    11.75   26.0    58                                                 B-4400                                                               24       EPICLON    5       5.3     59                                                 B-4400                                                               CONTROL.sup.1                                                                          --         --      87      70-78.sup.2                               ______________________________________                                         .sup.1 GEON 110 × 450 PVC homopolymer (I.V. = .95) plasticized with     110 phr TONE 0240                                                             .sup.2 Typical range for PVC homopolymer compositions with polymeric          plasticizer                                                              

EXAMPLES 25-27

Polymer blends were prepared utilizing the functionalized base polymersof the present invention and a coreactive polyurethane, e.g. ESTANE®5714, a polyether urethane available from The B. F. Goodrich Company. Toa two roll mill heated to 300° F. was added 100 parts of a hydroxylcontaining base polymer resin (2.5 mole % hydroxyl content) comprising avinyl chloride/2-hydroxyethyl acrylate copolymer (4.5 wt. % 2-HEA), 9.3to 13.0 phr of a cyclic polyanhydride (EPICLON B-4400, wt. % was keptconstant relative to total wt. of the composition) and 3.0 phr of tinstabilizer. The ingredients were milled for 2 to 5 min. to allowfunctionalization to take place. To the functionalized base polymer wasthen added the coreactive polyurethane in the ratios indicated in TableV and milled for an additional 5 min. The polymer blend was pressed intoa sheet and specimens were taken in accordance with the various testsset forth in Table V.

                  TABLE V                                                         ______________________________________                                                   25     26       27       Control.sup.1                             ______________________________________                                        Base Polymer/                                                                              60/40    50/50    40/60  50/50                                   Polyurethane Ratio                                                            Brittleness Temp.                                                                          -51      -56      -55.5  -60.5                                   (°C.)                                                                  (ASTM D-746)                                                                  Tear Resistance                                                                            728      625      537    512                                     (lbs/in)              (±19)        (±5)                                 (ASTM D-1004)                                                                 Tensile at Break (psi)                                                                     4084     3449     2881   2687                                    (ASTM D-412)                                                                  Elongation (%)                                                                             172      182      220    106                                     (ASTM D-412)                                                                  100% Modulus (psi)                                                                         3528     2956     2315   2667                                    (ASTM D-412)                                                                  Yield Stress (psi)                                                                         4099     3457     2887   2613                                    (ASTM D-412)                                                                  Yield Strain (%)                                                                           174      182      217    106                                     (ASTM D412)                                                                   Oil Resistance                                                                             +12.05   +13.20   +14.51 +15.04                                  (% vol.)                                                                      (ASTM D-2683)                                                                 ______________________________________                                         .sup.1 Base polymer was not functionalized with cyclic polyanhydride.    

EXAMPLES 28-34

Two different base polymers were prepared from vinyl chloride which wascopolymerized with acrylated caprolactone or 2-hydroxyethyl acrylate(2-HEA). The acrylated caprolactone base polymer contained approximately6.0 wt. % TONE M-100 acrylated caprolactone and had a 1.1 mole %hydroxyl content. The 2-hydroxyethyl acrylate base polymer contained 6.8wt. % 2-HEA and had a hydroxyl content of 3.8 mole %. The base polymerswere functionalized with the agents set forth in Table VI. Thecoreactive second moiety was a polycaprolactone diol of 2000 M.W. whichis commercially available from Union Carbide Corporation and sold underthe TONE 2241 trademark. The base polymers were functionalized andderivatized with the coreactive second moiety in accordance with theprocedures set forth in examples 10-15. Tin stabilizer and oxidizedpolyethylene lubricant were added in the amount of 2 phr and 0.15 phr,respectively.

                                      TABLE VI                                    __________________________________________________________________________               Examples                                                                      28     29     30     31     32    33  34                           __________________________________________________________________________    Functionalizing Agent                                                                    EPICLON                                                                              SMA 3000A                                                                            AC-32  --     EPICLON                                                                             AC-32                                                                             --                           Level (phr)                                                                              7.5    22.5   14     --     16    30  --                           Comonomer  TONE M-100                                                                           TONE M-100                                                                           TONE M-100                                                                           TONE M-100                                                                           2-HEA 2-HEA                                                                             2-HEA                        100% Modulus (psi)                                                                       2136   --     2654   1317   860   957 930                          Elongation (%)                                                                           186    40     165    277    135   108 239                          Tensile (psi)                                                                            2927   2453   3421   2005   1229  1039                                                                              1200                         Abrasion (mg)                                                                            178.7  184.2  169.0  89     108.6 149.9                                                                             333.2                        Hardness Shore A/D                                                                       89/54  92/57  92/53  86/37  60/23 64/23                                                                             88/38                        Oil Resistance                                                                           +11.77 +10.14 +8.71  +13.15 --    --  --                           (% Vol. Change)                                                               Brittleness Temp (°C.)                                                            -17.0  0      -11.5  -19.5  -18.5 -12.9                                                                             -11.5                        __________________________________________________________________________

What is claimed is:
 1. A process for the production of a crosslinkedcopolymer containing an internally bound processing aid comprising thesteps of:(a) reacting a functionalized base polymer, said functionalizedbase polymer comprising the reaction product of a hydroxyl containingvinyl halide base polymer and a cyclic polyanhydride functionalizingagent, whereby the functionalizing agent covalently bonds to the basepolymer through a reaction between a hydroxyl group(s) on the basepolymer and a cyclic anhydride group(s) on the functionalizing agent,wherein the functionalizing agent after bonding to the base polymer hasa free cyclic anhydride group(s) available for further reaction, and aprocessing aid coreactive therewith thereby obtaining a base polymerhaving the processing aid bonded thereon, and said bonded processing aidhaving at least one pendant functional group available for furtherreaction with a cyclic polyanhydride functionalizing agent; (b) reactingwith the product obtained in step (a) a cyclic polyanhydridefunctionalizing agent wherein said functionalizing agent after bondingretains free cyclic anhydride group(s) available for further reaction;and (c) reacting the anhydride functionalized product of step (b) with abase polymer selected from the group consisting of hydroxyl containingvinyl halide polymers, base polymers having a coreactive processing aidbonded thereon and mixtures thereof, wherein each of steps (a)-(c) beingconducted under anhydrous melt blending conditions.
 2. The process ofclaim 1 wherein the hydroxyl containing vinyl halide base polymercomprises the reaction product of:(a) a vinyl halide monomer; and (b) atleast one other ethylenically unsaturated monomer having at least onependant hydroxyl functional group.
 3. The process of claim 2, whereincomponent (a) is vinyl chloride and component (b) is selected from thegroup consisting of hydroxyalkyl acrylates, hydroxyalkyl methacrylates,and acrylated caprolactones, glycidyl acrylate and glycidyl methacrylateand mixtures thereof.
 4. The process of claim 3, wherein the acrylatedcaprolactone is represented by the following average formula: ##STR7##wherein R is hydrogen, lower alkyl or phenyl, R₁ and R₂ areindependently alkylene of 1 to about 8 carbon atoms and n is 1 to
 20. 5.The process of claim 4, wherein R is hydrogen, R₁ is ethylene, R₂ ispentylene and n is 1 to
 20. 6. The process of claim 2, wherein component(b) is present in the amount of about 1 to 49 percent by weight of thebase polymer composition.
 7. The process of claim 2, wherein thehydroxyl content ranges from about 0.1 to about 25 mole percent.
 8. Theprocess of claim 2, wherein component (b) is present in the amount ofabout 1 to 20 percent by weight of the base polymer composition.
 9. Theprocess of claim 2, wherein the hydroxyl content ranges from about 0.5to about 15 mole percent.
 10. The process of claim 1, wherein thefunctionalizing agent is selected from the group consisting of3,3',4,4'-benzophenone tetracarboxylic dianhydride;1,2,4,5-benzene-tetracarboxylic anhydride;3,4,3',4'-biphenyltetracarboxylic dianhydride;5-(2,5-dioxotetrahydro-3-furanyl)-3-cyclohexene-1,2-dicarboxylicanhydride; 5-isobenzofurancarboxylic acid,1,3-dihydro-1,3-dioxo-1,2-ethanediyl ester; 5-isobenzofurancarboxylicacid, 1,2-dihydro-1,3-dioxo-1,2-ethanediyl ester;5-isobenzofurancarboxylic acid,1,3-dihydro-1,3-dioxo-,2-(acetyloxy)-1,3-propanediyl ester;styrene/maleic anhydride copolymer; vinyl ether/maleic anhydridecopolymer; alkylene/maleic anhydride copolymers; cycloalkylene/maleicanhydride copolymers; maleic anhydride/alkyl acrylate and methacrylatecopolymers; maleic anhydride/acrylamide copolymer.